The present invention relates to a step-in snowboard binding in particular; a step-in snowboard binding designed to hold a boot by its sides.
A binding such as this is disclosed in U.S. Pat. No. 5,871,226, the content of which is incorporated by reference. This binding allows the boot to be held firmly when there is snow or ice present on the baseplate and when this snow or this ice melts and the boot tends to drop, the difference in height of the boot is automatically taken up by the binding. Furthermore, the locking element provides a firm grip, without elastic play, and without the jaw having to be acted upon by a powerful spring in order to achieve this. What happens is that the jaw is held pressed against the boot by the locking element, it being possible for this locking to be provided by appropriate shapes, without there being the need to have a powerful spring acting on the locking element. A binding such as this avoids the drawbacks of the bindings of the prior art, such as the bindings described in U.S. Pat. No. 4,973,073, the content of which is incorporated by reference, and U.S. Pat. No. 4,097,062, the content of which is incorporated by reference.
Other sources disclose bindings with two lateral jaws. A binding such as this is disclosed in document U.S. Pat. No. 6,053,524, the content of which is incorporated by reference, for a monoski. Another binding is disclosed in document WO 96/26 774, the content of which is incorporated by reference.
In the binding according to U.S. Pat. No. 5,871,226, the content of which is incorporated by reference, the jaw is urged by a return spring and the wedge-shaped locking element is also used as a means for holding the jaw in the open position, the jaw pressing against the end of the locking element. This locking element is therefore constantly pressed against the cam of the jaw and, when the boot is being put into the binding, the jaw has first of all to push back the locking element. In the open position, as the cam presses via a rounded portion against an (also rounded) portion of the end of the locking element, wear of the contracting surfaces is likely to cause the jaw to become locked in the open position.
Therefore, what is needed is a step-in binding which overcomes these drawbacks.
The step-in binding is provided in which the jaw is equipped with a return spring tending to keep its jaw in its open position, and the jaw and the locking element comprise collaborating means for keeping the locking element away from its locking position when the jaw is raised and as long as the jaw has not at least approximately reached a position likely to be a position for retaining the boot. The jaw is therefore not held in the open position by the locking element, but by its return spring. It therefore does not carry any risk of being closed inadvertently. Furthermore, in its first phase of closure, before it has at least approximately reached a position likely to be a boot-retaining position, the locking element does not in any way impede the jaw-closing movement.
The object of the invention is to produce a step-in snowboard binding, in which the jaw, or jaws, are not impeded in their open position by the locking element and do not carry the risk of being closed inadvertently when no boot is present.
According to a first embodiment of the invention, the locking element is in the form of a peg and the guide for this peg is directed at least approximately vertically.
According to one embodiment, the peg can rotate and is fitted with at least one radial arm which rotates as one with the peg, resting, via its end, on a stop when the jaw is in the raised position, the jaw being secured to an auxiliary cam retaining the radial arm in this pressing position, the shape of the cam-shaped part being such that it releases the radial arm when the jaw is lowered, allowing the locking peg to move into the locking position.
The jaw is preferably mounted in a mount forming a roughly vertical guide for a set of moving parts carrying said peg and the jaw comprises a means for deliberately raising this set of moving parts, actuation of which allows the jaw to be raised and the radial arm of the peg to be returned to a position resting against the mount.
The binding is preferably equipped with two opposed jaws which are kinematically connected so that the two jaws can be lowered simultaneously so that one jaw cannot close without the other jaw closing also. Mechanical play is advantageously provided in the kinematic link between the jaws so as to take account of a slightly oblique position of the boot as the result of snow or ice being present under the boot.
According to another embodiment, the cam-shaped part of the jaw has a lateral wall forming a stop for the locking element so as to keep it away from its locking position and a cutout forming a circumferential stop, and the locking element consists of a finger which can move at least approximately parallel to the axis of rotation of the jaw and is in the shape of a wedge pressing against the circumferential stop as it enters said cutout after the jaw has rotated a certain amount. Like in the first embodiment, the opposite retaining element advantageously consists of a second jaw identical to the first and the two locking fingers are kinematically linked. In this case too, mechanical play is advantageously built into this kinematic link.